安装mysql 参照python篇一键安装lnmp。安装完之后再按照下面修改密码，修改配置文件，否则安装的时候就修改配置文件会出错。 注意：这也是二进制安装mysql。另一种二进制安装容易出错，生产环境不要用rpm包安装，会出问题，测试过安装msyql不要改里面的字符类型，否则安装时候报错。等安装完后再修改 2、查看初始化的密码： 初始化mysql时生成的密码 初始化mysql 2018-11-27T07:28:39.407117Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2018-11-27T07:28:40.069251Z 0 [Warning] InnoDB: New log files created, LSN=45790 2018-11-27T07:28:40.181277Z 0 [Warning] InnoDB: Creating foreign key constraint system tables. 2018-11-27T07:28:40.194608Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 0fbb7543-f216-11e8-9f31-000c29c231f7. 2018-11-27T07:28:40.195834Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened. 2018-11-27T07:28:40.197256Z 1 [Note] A temporary password is generated for root@localhost: 8YuFFueq4P!o 8YuFFueq4P!o 就是密码 3、重置为复杂密码 3.1、配置免密登录 、重启mysql、登录mysql 在[mysqld]下面添加skip-grant-tables [root@ecs-03 mysql]#service mysqld stop [root@ecs-03 mysql]# vi /etc/my.cnf [mysqld] skip-grant-tables #跳过密码 重启数据库 [root@ecs-03 mysql]# systemctl restart mysqld 一条命令执行以上步骤如下 systemctl stop mysqld && sed -i '/mysqld/a skip-grant-tables' /etc/my.cnf && systemctl restart mysqld 登录数据库，下面直接回车 不用输入密码 [root@ecs-03 mysql]# mysql -u root -p Enter password: [root@ecs-02 mysql]# mysql -u root -p Enter password: Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 3 Server version: 5.7.22 MySQL Community Server (GPL) Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or 'h' for help. Type 'c' to clear the current input statement. mysql> 3.2、 修改root数据库账号密码方式一（推荐） 修改当前用户为root mysql> use mysql; Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Database changed mysql> select host, user from user; +---------------+---------------+ | host | user | +---------------+---------------+ | % | root | | 192.168.0.% | root | | 192.168.0.1.% | root | | localhost | mysql.session | | localhost | mysql.sys | | localhost | root | +---------------+---------------+ 6 rows in set (0.00 sec) mysql> update user set host='%' where user='root'; ERROR 1062 (23000): Duplicate entry '%-root' for key 'PRIMARY' #不用管，没有影响，直接下一步 mysql> flush privileges; Query OK, 0 rows affected (0.02 sec) 重启数数据，否则不生效 systemctl restart mysqld #等操作完下面一起重启 授予root用户给其他用户授权的权限 update mysql.user set Grant_priv='Y' where User='root' and Host='%'; flush privileges;（刷新权限） 修改root密码、开启远程连接授权 mysql> flush privileges; Query OK, 0 rows affected (0.02 sec) mysql> grant all privileges on *.* TO 'root'@'%' identified by 'jenkins@123' with grant option; Query OK, 0 rows affected, 1 warning (0.02 sec) mysql>grant all on *.* to root@'localhost' identified by 'jenkins@123' with grant option; mysql> alter user 'root'@'localhost' identified by 'jenkins@123'; mysql> flush privileges; Mysql>exit 修改后把kip-grant-tables注释掉重启mysql systemctl stop mysqld && sed -i 's/skip-grant-tables/#skip-grant-tables/g' /etc/my.cnf && systemctl restart mysqld 3.3、修改root数据库账号密码方式二 mysql> set password=password("youpassword"); mysql> alter user 'root'@'localhost' identified by '123456'; ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement 报错不用管，接着输入下面 mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.02 sec) mysql> GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' identified by 'zihao@666'; Query OK, 0 rows affected, 1 warning (0.02 sec) mysql>grant all on *.* to root@'localhost' identified by 'zihao@666'; mysql> alter user 'root'@'localhost' identified by 'zihao@666'; mysql> FLUSH PRIVILEGES; 修改后把kip-grant-tables注释掉重启mysql systemctl stop mysqld && sed -i 's/skip-grant-tables/#skip-grant-tables/g' /etc/my.cnf && systemctl restart mysqld 3.4、用修改后的密码登录mysql [root@bogon local]# mysql -u root -pzihao@666 mysql: [Warning] Using a password on the command line interface can be insecure. Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 2 Server version: 5.7.22-log MySQL Community Server (GPL) Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or 'h' for help. Type 'c' to clear the current input statement. mysql> 4、重置为简单版密码 4.1、配置免密登录 、重启mysql、登录mysql [root@ecs-03 mysql]# vi /etc/my.cnf 删掉：kip-grant-tables ， 添加：validate_password=off :可以修改成简单的密码 然后重启： [mysqld] validate_password=off #skip-grant-tables 4.2、修改root数据库账号密码同上 5、修改字符为utf8mb4 安装完成后需要修改字符满足生产需求，之前公司就是总是出现乱码，后来改成utf8mb4问题解决 临时修改 mysql>show variables like 'character%'; mysql>set character_set_database=utf8mb4; mysql>set character_set_server=utf8mb4; 永久修改 systemctl stop mysqld && sed -i -e 's/character-set-server = utf8/character-set-server = utf8mb4/g' -e '/client/ adefault-character-set = utf8mb4' -e '$adefault-character-set = utf8mb4' /etc/my.cnf && systemctl start mysqld 注意：character_set_database=utf8mb4 这句话不要写到配置文件里面，否则启动报错 要达到的效果 mysql> show variables like 'character%'; +--------------------------+----------------------------------+ | Variable_name | Value | +--------------------------+----------------------------------+ | character_set_client | utf8mb4 | | character_set_connection | utf8mb4 | | character_set_database | utf8mb4 | | character_set_filesystem | binary | | character_set_results | utf8mb4 | | character_set_server | utf8mb4 | | character_set_system | utf8 | | character_sets_dir | /usr/local/mysql/share/charsets/ | +--------------------------+----------------------------------+ 8 rows in set (0.01 sec)